v4l2object: Fix regression in offset extrapolation

When extrapolating the offset, we need to use the extrapolate
stride rather then the base stride. This should fix support for format
with more then two planes (I420, Y42B, etc).
matroskamux: fix the memory leak of language attribute

https://bugzilla.gnome.org/show_bug.cgi?id=728418
rtpjitterbuffer: don't stop looping if event found in the queue

If we are inserting a packet into the jitter queue we need to keep
looping through the items until the right position is found. Currently,
the code stops as soon as an event is found in the queue.

Regarding events, we should only move packets before an event if there
is another packet before the event that has a larger seqnum.

Fixes https://bugzilla.gnome.org/show_bug.cgi?id=730078
rtpsession: timeout internal sources that are inactive for a long time and send BYE
rtpsession: unify nested if clauses
rtpsession: cleanup sources that have sent BYE
rtpsession: remove unused if branch

1) sources that have sent BYE in the past cannot be senders, since
they would have timed out to being receivers in the meantime...
2) sources that have sent BYE are now being removed earlier inside
this function
tests/check: rtpsession: test internal sources timing out
rtpbin: update rtp encoder/decoder docs

Use %u in RTP encoder/decoder pads to match other rtpbin pads.

https://bugzilla.gnome.org/show_bug.cgi?id=730146
v4l2bufferpool: Also update num_buffers for import cases

https://bugzilla.gnome.org/show_bug.cgi?id=730207
v4l2bufferpool: Don't deactivate otherpool

We should not stop the otherpool unless we also stop our own
pool, otherwise it will never get restarted.

https://bugzilla.gnome.org/show_bug.cgi?id=730207
v4l2allocator: Fix use of atomic active marker

https://bugzilla.gnome.org/show_bug.cgi?id=730207
v4l2transform: Flush buffer pools on flush stop

https://bugzilla.gnome.org/show_bug.cgi?id=730207
v4l2: Split flush in start/stop_streaming

This allow calling start streaming later for capture device. Currently it breaks
in dmabuf-import because downstream is holding a buffer that will only be
released after stream-start.

https://bugzilla.gnome.org/show_bug.cgi?id=730207
v4l2transform: Don't leak pool if activation failed

https://bugzilla.gnome.org/show_bug.cgi?id=730207
v4l2videodec: Don't lock the decoder when stopping task

That src pad task may need to take the lock when being pulled
down. takeing that lock can lead to a deadlock.

https://bugzilla.gnome.org/show_bug.cgi?id=730207
v4l2videodec: Print the flow return causing the loop to leave

https://bugzilla.gnome.org/show_bug.cgi?id=730207
v4l2videodec: Handle start_streaming error

https://bugzilla.gnome.org/show_bug.cgi?id=730207
v4l2bufferpool: Update pool limit with hardware requiremenst

If the driver need more buffers than requested by the config,
update the pool min/max values. The minimum value for the pool
could be provided either by the driver or by the pool. This is
best effort for drivers that don't support
CID V4L2_CID_MIN_BUFFERS_FOR_CAPTURE.

https://bugzilla.gnome.org/show_bug.cgi?id=730200
v4l2: Cleanup M2M properties

M2M devices were sharing the same properties as src and sink. Most of
these made no sense. This patch reduces the number of propeties and
makes io-mode clearer by having capture-io-mode and output-io-mode. This
also accidently fixed a bug in gstv4l2transform io-mode code, where the
capture io-mode could not be set.

https://bugzilla.gnome.org/show_bug.cgi?id=729591